Symptoms, Causes, and Treatments

Diarrhea is a condition that results in frequent, runny bowel movements. Most people will have several episodes of diarrhea for various reasons during their life. In most instances, it is short-lived and does not cause problems beyond a few necessary sprints to the bathroom. Even though it is rarely dangerous, the loose stools can be an enormous inconvenience and often occur with other miserable symptoms that require a day or two of rest.  


If you have diarrhea, you may also experience nausea, vomiting, or abdominal pain in addition to loose stools. Diarrhea is usually just a symptom of an underlying ailment. There are many reasons you might come down with this unpleasant condition. A thorough medical history and evaluation of your symptoms will help your doctor determine the cause of your diarrhea and an appropriate treatment plan.  


Diarrhea can be chronic or acute. Unknown food allergies, genetic disorders, or lactose intolerance can cause long-term symptoms if you do not get diagnosed and treated. Bacterial, viral, or parasitic infections tend to be more acute than their chronic counterparts and usually resolve on their own. Whatever the reason you find yourself tethered to the nearest toilet, our licensed doctors are available to address your concerns about your GI health.  





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The Process of Diarrhea 

Your gastrointestinal (GI) tract is a passageway of food and drink that starts at your mouth and ends at your anus. It includes your esophagus, stomach, and intestines. Your GI tract maintains a delicate balance of absorbing the right amount of electrolytes and water while secreting or removing the rest. Diarrhea occurs when this balance is thrown off either from decreasing the amount your intestines absorb or increasing the amount they remove.  


When you consume food or ingredients that draw water into the intestines instead of being absorbed, the excess fluid will cause loose or watery bowel movements. This type of diarrhea is called osmotic and results from conditions like lactose intolerance or reactions to certain ingredients like artificial sweeteners. Alternatively, secretory diarrhea occurs when your body secretes or releases excessive amounts of electrolytes or fluids into the intestines. Infections are often the cause of this type of diarrhea. 


Whether you have osmotic or secretory diarrhea, both tend to be miserable. You will have increased stool output with a significant decrease in stool firmness, requiring frequent bathroom stops that limit your ability to perform daily activities. In some instances, diarrhea is severe enough to have a watery consistency. For those still in diapers, the enzymes found in stool meant to help digest food irritate the skin and cause painful diaper rashes.  

Chronic Versus Acute Diarrhea

There are two main classifications of diarrhea, acute and chronic. Acute is generally defined as a rapid onset of loose bowel movements three or more times per day for less than 14 days. While chronic diarrhea occurs when diarrhea lasts beyond 14 days.i Infectious diarrhea, or diarrhea that can spread from person to person, tends to be acute. In contrast, chronic diarrhea tends to have noninfectious etiologies or causes.1  


If you have chronic diarrhea, you will need to determine the underlying cause so you can treat your condition and reduce your symptoms. Most people suffering from chronic diarrhea will maintain routine daily activities once they get diagnosed and initiate treatment. You will need to work closely with a doctor to manage your condition if you have chronic diarrhea.  


Most cases of acute diarrhea resolve independently and do not require treatment beyond resting at home and replenishing liquids. However, if you or a child has diarrhea and cannot maintain hydration, you should see a doctor. You may need IV fluids and additional treatment. If you are confused, lethargic, or losing consciousness, seek immediate medical attention.  


Inflammatory Bowel Disease 


Inflammatory bowel disease is a blanket term describing disorders that cause chronic inflammation of the intestines. The two types are ulcerative colitis and Crohn's disease. Both conditions will cause chronic diarrhea but are manageable with appropriate treatment. Although the disease is lifelong, most people will continue to live normal lives with certain modifications.  


Symptoms of Inflammatory Bowel Disease 


Ulcerative colitis causes inflammation and ulcers on the superficial lining of the large intestine or colon. However, the inflammation from Chron's disease can be anywhere along the digestive tract, from the mouth to the anus. Both can range in severity, with periods of remission where no symptoms are present. During symptomatic periods you may have:  


• Severe diarrhea 

• Bowel urgency 

• Constipation 

• Gas, cramps, and bloating 

• Blood or mucous in the stool 

• Decreased appetite 

• Weight loss 


What Causes Inflammatory Bowel Disease? 


Doctors do not know the cause, but there appears to be a genetic factor. If a close relative has one of these diseases, you are also more likely to have one. Scientists also suspect that bowel damage found in inflammatory bowel disease may result when the immune system responds incorrectly to specific environmental triggers. Simply put, your immune system attacks something like a harmless virus inside your gut, resulting in inflammation.  


How Is Inflammatory Bowel Disease Diagnosed? 


Diagnosing inflammatory bowel disease requires your doctor to rule out other potential origins of your symptoms. You may need to provide blood and stool samples for laboratory testing and undergo specific endoscopic procedures that allow your doctor to view inside your intestines.  


During an endoscopy, your doctor inserts a small camera into your rectum to look for signs of inflammation. At this time, they may retrieve a small tissue sample for the lab to evaluate. Different diagnostic methods are less invasive, like x-rays and MRIs. Your doctor can also gather images by having you swallow a capsule with a camera inside. 


Treating Inflammatory Bowel Disease 


Treatment will look different from patient to patient. The goal is to decrease bowel inflammation, encourage periods of remission, and reduce flair-ups. There are several classes of medications that control inflammation and reduce symptoms. The medicine you take will depend on the type of inflammatory bowel disease you have and the symptoms. 


You may need to try several medications to find one that works for you. Your doctor will work closely with you to get the best treatment for your condition. In some instances, your doctor will prescribe you an antibiotic if they believe you have developed an intestinal infection. Rarely, in severe cases, patients will require surgery to remove diseased tissue.  


Celiac Disease 


Celiac disease is a chronic condition caused by an allergic reaction to a protein called gluten found in wheat, barley, and rye. If you have celiac disease and are exposed to this protein, the subsequent immune reaction damages and irritates the lining of the small intestines resulting in symptoms.  


Symptoms of Celiac Disease 


Symptoms can vary in severity, frequency, and between patients. Most people experience diarrhea, constipation, weight loss, bloating, abdominal pain, or nausea when exposed to gluten. Some celiac patients will also experience non-intestinal symptoms like mouth ulcers, skin rashes, joint pain, or fatigue.  


How is Celiac Disease Diagnosed? 


To get a diagnosis, your doctor will start by taking your medical history and reviewing your signs and symptoms. They will need to order lab tests to rule out other digestive disorders or rule in celiac disease. If your blood tests suggest you have this condition, your doctor may want to get a biopsy, or small tissue sample, of your intestines. A pathologist will use a microscope to study your tissue sample for signs of celiac disease.  


Treating Celiac Disease 


The only way to treat celiac disease is with strict gluten avoidance. Even small amounts can cause painful symptoms. If left untreated, persistent gluten exposure will damage the intestines and result in malabsorption and nutritional deficiencies. These deficiencies can affect bone health and cause symptoms related to vitamin and mineral deficits. With prolonged exposure to gluten, you could also develop additional complications like lactose intolerance or anemia.  


Celiac disease does not have a cure and will never go away. You will need to remove gluten from your diet for your entire life. Once you no longer consume gluten, your intestines will heal, and symptoms will improve. In the absence of exposure, you should remain symptom-free. However, as with many food allergies, accidental exposure is a possibility.  


Irritable Bowel Syndrome (IBS) 


People with IBS have chronic diarrhea and other uncomfortable GI symptoms without bowel tissue damage. If your doctor were to take a tissue sample of your intestines, they would appear normal even while symptomatic. There are multiple types that are classified based on your symptoms. The three forms are IBS with constipation, IBS with diarrhea, and IBS with mixed bowel habits where you have alternating constipation and diarrhea.  


Symptoms of Irritable Bowel Syndrome 


Symptoms can range from mild to severe, with abnormal periods punctuated by normal bowel habits. Symptoms can be unpredictable and contradictory, with diarrhea one day and constipation the next. Although IBS is not dangerous, it can restrict your normal activities and decrease your quality of life. Symptoms are:  


• Diarrhea  

• Constipation 

• Abdominal pain and cramping 

• Bloating and gas 

• Bowel urgency 


What Causes Irritable Bowel Syndrome? 


There is no single known cause, but there are aspects that increase your chances of a diagnosis. One major risk factor for IBS is falling ill with an acute intestinal infection. Research has shown that 4 to 36% of people with infectious gastroenteritis will develop post-infectious irritable bowel syndrome.ii 


Individuals with a history of emotional trauma or mental health conditions are also more likely to have IBS.iii Whatever the cause and whatever your risk factors, researchers believe that somehow a disconnect between the brain and the gut occurs that leads to intestinal dysfunction.  


How Is Irritable Bowel Syndrome Diagnosed? 


Because you cannot test for IBS, a diagnosis can be challenging. Your doctor will start with a thorough physical exam and medical history to narrow down the possibilities for your diarrhea. Next, your doctor may request blood and stool samples to rule out different causes of chronic diarrhea. Once your doctor eliminates other diagnoses and your medical history meets the criteria for IBS, they will develop a treatment plan tailored to you.  


Treating Irritable Bowel Syndrome 


There is no cure, but you can manage the symptoms. The treatment method will depend on your type of IBS and its severity. Dietary changes, education, and medication are ways to control and reduce its effects on your life. Start with a food journal. Even if you have not seen a doctor yet, the information you gather from journaling can aid your diagnosis and treatment.  


Infectious Diarrhea 


Infectious diarrhea usually resolves within a week or two with minimal intervention. In most cases, treatment is primarily supportive care and is not dependent on identifying the pathogen. However, in severe or persistent infections, your doctor may need to determine the microbe so they can initiate specialized treatment. If needed, your doctor will order laboratory testing to establish if your diarrhea results from a bacteria, virus, or parasite.  


Symptoms of Infectious Diarrhea 


Symptoms vary depending on the pathogen causing the infection. Additionally, each patient will experience their illness differently, even when afflicted with the same bug. If you have infectious diarrhea, you may have any combination of the following symptoms:  


• Diarrhea (can be watery) 

• Fever  

• Stomach cramps 

• Nausea and vomiting 

• Bloating 

• Bloody stools (depends on pathogen)  

• Headache  

• Muscle aches 


There is enough overlap and similarities between the many causes of infectious diarrhea that identifying the microbe based on symptoms alone is nearly impossible. 


Bacterial Causes of Infectious Diarrhea 


Many species of bacteria cause infectious diarrhea. Some are spread from person to person, while others are foodborne pathogens. Regardless of the microbe irritating your gut, you will likely have a day or two of hardship ahead of you once exposed to them. Most people will recover fine, but the very old, very young, and immunocompromised are at greater risk of hospitalization. 


Salmonella, E. coli, Campylobacter, Shigella, and Staph aureus can all spread from eating contaminated food. Salmonella, E. coli, and Campylobacter occur when you eat food contaminated with animal feces that contains the bacteria. However, E. coli is the only of those three that spread easily from person to person once infected.  


Humans are the primary reservoir for Shigella. If you get Shigella, you get it by ingesting microscopic stool particles from an infected individual. This route of transmission is called fecal-oral. It occurs when a healthy individual consumes contaminated food or touches a contaminated surface and then puts their hands in their mouth. Food poisoning from staph does not transmit between people and is strictly foodborne.  


C. difficile is unique from the other bacterial causes because it usually occurs after antibiotic use, especially if the patient is a resident of a long-term care facility or hospitalized. Many people are colonized with C. diff but do not exhibit symptoms. If you are an asymptomatic carrier of C. diff, treatment is unnecessary.iv  If you are infected, as opposed to colonized, you will exhibit symptoms and need treatment.  


Viral Causes of Infectious Diarrhea 


Viral infectious diarrhea occurs when a healthy individual ingests microscopic particles of an infected person's vomit or stool. Transmission occurs when someone who is actively shedding the virus deposits tiny amounts of fecal matter onto food or surfaces that an uninfected person later encounters. This type of transmission is often a result of poor hand hygiene.  


Most people who get viral infectious diarrhea recover fine without incident, but the younger or older you are, or if you are immunocompromised, your risk of complications increases. Norovirus, Rotavirus, and Adenovirus are a few frequent offenders that spread quickly between people.   


Once sick with Norovirus, you can shed billions of viral particles, and it only takes just a few to make someone sick.v Unfortunately, Norovirus immunity is short-lived, and you can contract it more than once.  


Rotavirus is dangerous for young children but tends to be mild in adults. An oral vaccine that protects against Rotavirus is part of the routine childhood vaccination schedule, making Rotavirus less of a concern. 


Adenovirus can cause many illnesses, from the common cold to pink eye to infectious diarrhea. In addition to a fecal-oral route, adenovirus diarrhea can spread less commonly in recreational water, like swimming 


Parasitic Causes of Infectious Diarrhea 


Parasites cause an array of illnesses, but when it comes to parasites that cause diarrhea and plague communities across the United States, Giardia and Cryptosporidium are frequent flyers. Both can make you sick if you swallow contaminated water from pools, water parks, lakes, and rivers. Cryptosporidium can also find its way to food, surfaces, or your hands.  


Treatment for Infectious Diarrhea 


For most cases, rest and supportive care are sufficient. You will lose vital fluids through vomiting, diarrhea, and sweating; replenishing them is necessary to avoid dehydration. If you cannot keep fluids down, try small amounts of clear liquid at frequent intervals. You may need to cease oral intake and let your stomach rest for several hours before attempting hydration.  


Let the infection run its course and stay home until you are symptom-free for 24 to 48 hours to prevent spreading your illness to others. Most people will feel good enough to return to daily activities within a week, sometimes less. If the diarrhea is persistent, your doctor may need to identify the pathogen and initiate specific treatment.  


When you begin to feel better and can drink without vomiting or diarrhea, start adding small amounts of bland food in addition to the clear fluids. Try a bite or two and wait to ensure your stomach can handle it before attempting more food. Take it slow and continue adding more food as your stomach can tolerate.  


If you have a GI illness and are unsure how to manage your symptoms or if your diarrhea has persisted beyond a couple of days, contact a doctor. Your physician can answer any questions and offer support to aid in your recovery. Seek immediate treatment if your symptoms are severe, you have intense pain, your fever is persistent or high, or you notice blood in your vomit, stool, or urine.  


Preventing Infectious Diarrhea 


Despite public health officials' best efforts, infectious diarrhea continues to spread. These microbes have ensured their survival by evolving in ways that guarantee they move from person to person. You can still shed them even after you feel better. Hand washing and personal hygiene are critical for that reason, but even if we do our best, it is sometimes not good enough.  


Personal hygiene is far from a top priority when your body rejects last night's dinner against your will, and your stomach contents escape in any way possible. If you're too sick to stand, let alone clean up after yourself, the pathogen on board your body is sure to liberate itself and eventually hitch a ride with another unfortunate person.  


The best thing society has done to prevent infectious diarrhea is improve sanitation. Measures like access to safe drinking water, adequate hand washing, good food hygiene, and the rotavirus vaccine have all reduced diarrheal disease. Do the best you can to isolate yourself in times of illness and even if you feel healthy, always wash your hands.  


Other Causes of Diarrhea 


The list of reasons someone gets diarrhea is long. Beyond allergies, digestive tract disorders, and infectious diseases, there is still more. From medication side effects to normal gut bacterial overgrowth, people get diarrhea.  




Researchers have tied over 700 drugs to diarrhea, but the biggest offenders are antibiotics, laxatives, nonsteroidal anti-inflammatories, and some medicines used to treat heartburn or stomach ulcers. vii Less commonly chemotherapy agents, medications that suppress the immune system, or metformin to treat diabetes.viii You may also find that particular vitamins or minerals upset your stomach. 


Although a lot of medications list diarrhea as a potential side effect, diarrhea is not a guaranteed result. Most people will tolerate these medicines without incident. Still, knowing the side effects of your prescriptions or over-the-counter drugs is important in case you experience any problems. Talk to your doctor before stopping medication or before starting something new.  


Lactose Intolerance 


If you are lactose intolerant, you have insufficient amounts of an enzyme called lactase. The lactase enzyme has the crucial job of breaking down a sugar found in dairy called lactose. The severity of your lactose intolerance is proportional to the amount of lactase in your digestive tract. The less lactase your body makes, the more severe your symptoms.  


When you are deficient in lactase, lactose can move freely through your digestive tract without breaking down into a more digestible form. The excess lactose pulls fluid into your bowels, producing diarrhea. Gas and bloating can also occur when bacteria from your gut ferment the excess lactose. 


Although lactose intolerance is not dangerous, it can make it difficult to enjoy a variety of foods. If you are lactose intolerant, you may have gas, bloating, nausea, diarrhea, and stomach cramps after consuming dairy. There is no cure, but it is relatively easy to control your symptoms. 


Lactose avoidance or over-the-counter lactase enzymes are the easiest ways to improve symptoms. Because most people make at least some lactase, you might be able to adjust your lactose intake and find an amount you can consume comfortably. If you remove lactose from your diet but still exhibit symptoms, your diarrhea might have another origin.  


Small Intestinal Bacterial Overgrowth (SIBO) 


Your digestive tract relies on good peristalsis (unidirectional movement of digestive contents), antibodies, bile, gastric acid, enzymes, and a complex population of bacteria to maintain a healthy environment. Failure of any one of these pieces can throw off your gut's bacterial balance and result in small intestinal bacterial overgrowth (SIBO). 


Symptoms can be persistent, chronic, and prevent you from engaging in normal daily activities. Because various species of bacteria live inside your gut, your symptoms will depend on which species has outcompeted the others. SIBO can look different from patient to patient. If you are suffering from SIBO, you might experience:  


• Chronic diarrhea  

• Unintentional weight loss 

• Nutritional deficiencies 

• Abdominal pain and distension 

• Nausea 

• Bloating and gas 


Treating SIBO can be challenging because the cause can be complex and difficult to pinpoint. But there are various treatment options. Your doctor will likely take a multi-pronged approach that involves a combination of managing symptoms through diet while also taking antibiotics.  


Although the medical community has not established a standard SIBO treatment, the antibiotic Rifaximin shows efficacy.ix Unfortunately, the medication is expensive, and many insurance companies do not cover the cost. SIBO can reoccur and may require multiple rounds of antibiotics. 


Contact a Doctor Today to Learn More About Diarrhea Causes and Treatments 

Contact a Doctor Today to Learn More About Diarrhea Causes and Treatments 


Most cases of diarrhea clear without treatment and require nothing more than rest and increased fluid intake. Other instances of diarrhea can drag on and lead to complications like malabsorption, weight loss, and dehydration. Understanding the origins of your diarrhea and initiating the proper treatment is essential to getting back to living your life again.  


There are many reasons you might succumb to upset bowels. Identifying the cause can take time. Be patient with the diagnostic process, and feel free to contact your doctor with any updates or changes. Advocate for yourself and always tell your doctor if your symptoms are not improving. You may need to change courses.  


Rest assured that regardless of the source of your upset stomach, a treatment plan is out there for you. Whether your diarrhea is chronic or acute, infectious or otherwise, there is relief. Contact one of our licensed physicians today to get you started on the path to healing.  

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